I think it look pretty good. ditch the shoes and you'll be able to get a little further back with your butt. you're starting in the right place for your height, if you want to advance to heavier weights do not artificially lower your start to comport with some oly lifting ideal.

I didnīt think it mattered much because my weights arenīt very high, but I tried again yesterday with flat non elastic shoes and I could notice the difference.
Felt much better. No backwards movement at all.